Cotton gram-negative bacteria

Gram negative bacteria are natural contaminants of fibrous plant material. In processes where cotton is agitated, i.e. during rapid machining, bacteria on the cotton fibers often become airborne, and the workers involved in dus areas may be exposed to concentrations of bacteria as high as 10 bacteria/m 51). 

There are large numbers of gram-positive and gram-negative bacteria and fungi in various materials associated with cotton. Table II lists studies giving an overall picture of the microbial (viable organism counts) content of various cotton dusts. A few pertinent references are summarized. 

Gram-negative Bacteria. The significant data are summarized in Table IV. Cinkotai et al. (11,12) showed that the prevalence of byssinotic symptoms correlated best with gram-negative rod counts in the total airborne dust from cardrooms of cotton mills. This correlation could be Increased by multiplying the bacterial counts by the years of exposure of the worker. These bacteria also correlated with the number of 2-4 ym particles and the amount of protease in the air. 

Endotoxin. Endotoxin is the lipopolysaccharide that comprises a major portion of the cell wall of the gram-negative bacteria. The endotoxins from each species of bacteria are different but the lipid A moiety is similar for the Enterobacterlaceae, and has a similar series of biological actions regardless of its source. The lipid A material is different in some of the gram-negative rods present in cotton (i.e. in the Pseudomonas species). This variety of compounds makes quantitation of endotoxin difficult. Hence, it is usually measured by its biological activity as compared to a standard endotoxin (usually that of E. coll). (See Table VIII.)... 

Content of Gram Negative Bacteria, Leaflike Trash and Total Trash in Materials Processed by Cotton Industries... 

Table 2. Average Counts for Total Bacteria and Gram-Negative Bacteria on Samples of Commercial Fiber from Four Major Regions of the U.S. Cotton Belt in the Crops of 1980, 1981, 1982, and 1984.

Morey, P., Fischer, J., and Rylander, R. (1983). Gram-negative bacteria on cotton with particular reference to climatic conditions. Am. Ind. Hyg. Assoc. J.. 44, 100-104. 

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